how to make leather backpack：Cut your pieces out of durable fabric, such as canvas. You can also make your backpack out of cotton or linen, but it may not be as durable. To make things easier later on, consider labeling the pieces with some dressmaker's chalk. Here are the pieces you need to cut:
Body: two 44 by 50-centimeter (17.32 by 19.69-inch) rectangles
Base: one 17 by 36-centimeter (6.7 by 14.18-inch) rectangle
Flap: two 24 by 24-centimeter (9.45 by 9.45-inch) squares
Shoulder straps: two 10 by 66-centimeter (3.94 by 25.99-inch) strips
Handle strap: one 10 by 24-centimeter (3.94 by 9.45-inch) strip
Round the corners of the flap pieces. Pin the two flap pieces together, with the right sides facing in. Use a glass and a pen to draw the curves first, then cut them out with a pair of scissors.
Sew the two flap pieces together using a 1-centimeter (0.4-inch) seam allowance. Sew along both of the side edges and the curved, bottom edge. Leave the top, straight edge open, so that you can turn the flap inside out.
Cut little notches into the curved edges. Be careful not to cut into the stitching. This will help reduce bunching and bulk when you turn the flap inside-out.
Turn the flap right-side-out, press it flat with an iron, then topstitch the edges. After you turn the flap inside out, use something thin and slender, like a pair of scissors, a chopstick, or a knitting needle, to push out the curves. Press the edges of the flap down with an iron using a heat setting suitable for the fabric. When you are done, topstitch all the way around the flap, about 6 millimeters (0.24 inches) from the edge. You can use a matching thread color, or a contrasting one.
For a fancier touch, pin some bias tape all the way around the edges, then top stitch it down.
You can topstitch the top, raw edge this time around, if you want to.
Fold the edges of the shoulder and handle strips in by 1 centimeter (0.4 inch), then press them flat with an iron. Turn the strips so that the wrong sides are facing you. Fold and press each of the long edges by 1 centimeter (0.4 inch). Do this for both of the shoulder straps and the handle strap. Leave the narrow edges alone.
Fold, press, and topstitch the shoulder and handle straps. Fold each of the strips in half, lengthwise. The folded edges should now be on the inside, and the right-side of the fabric should now be on the outside. Pin the edges in place, then topstitch along them, about 6 millimeters (0.24 inch) away from the edge. Do this for both of the shoulder strap pieces and the handle strap.
Pin and sew the body pieces together, leaving a 3-centimeter (1.19-inch) gap on each side for the cording. Pin the two body pieces together, with the right sides facing each other. Starting from the top-left corner, stitch down 5 centimeters (1.97 inches) along the long edge. Leave a 3-centimeter (1.19-inch) long gap, then continue sewing the rest of the way down to the bottom corner. Repeat for the right side.
Use a 1-centimeter (0.4-inch) seam allowance.
Do not sew along the bottom edge of the bag.
Press the seam allowances open. An easy way to do this is to turn the body piece inside out, and turn it so that one of the seams is on the ironing board. Run the iron through the tube, pressing the seam allowances open and flat. Repeat this for the other seam allowance, then turn the back inside out again so that the wrong side of the fabric is facing you.
Fold the top edge of the bag down twice to make the casing. Fold and press the top edge of the bag down by 1 centimeter (0.4 inch) first. Then, fold it down by 4 centimeters (1.58 inches), and press it again. Make sure that you are folding evenly all the way around the top edge of the bag.
Topstitch along the bottom edge of the casing, then turn the bag inside out. Sew as close to the bottom edge as you can—about 6 millimeters (0.24 inch). seam allowance. Use a color that matches your fabric; for a more interesting design, use a contrasting color. When you are done, turn the back inside out, so that all of the seams are on the inside, and the right side of the fabric is facing you.
Pin the shoulder straps and the handle strap to the top of the bag. Make sure that the bag is turned inside-out first, so that the right side of the fabric is facing you. Then:
Pin the shoulder straps 13 centimeters (5.12 inches) apart, just below the casing. The top edges should be facing top of the bag, and the bottom edges should be facing the bottom of the bag.
Pin the ends of the handle strap between the shoulder straps. The ends of the handle should be facing the top of the bag, and the loop of the handle should be facing the bottom of the bag.
Pin the flap on top of the shoulder and handle straps. Position the flap so that the top, raw edge is just below the casing, and aligned with the raw edges of the straps. The raw edge should facing the top of the bag, and the curved edge should be facing the bottom of the bag.
Stitch the flap in place, then fold flap upwards, and topstitch it again. Use a 1-centimeter (0.4-inch) seam allowance both times.
Pin the ends of the shoulder straps to the bottom of the bag, 18 centimeters (7.09 inches) apart. Make sure that you are only pinning them to the back of the bag. Do not pin them through both layers of fabric, or you won't be able to attach the base.
Cut the corners of the base piece so that you get a rounded rectangle. Fold the base into fourths. Use a glass to trace a curve on top of the loose (not folded) corner. Cut along the line that you drew, then unfold the base. You'll get a rounded rectangle.
Turn the back inside-out again, then pin the base to the bottom, and sew it in place. Turn the bag inside-out so that the wrong side of the fabric is facing you. Pin the base to the bottom of the bag. The long edges of the base should be at the front/back of the bag. The short edges of the base should be at the sides of the bag. Stitch the base in place using a 1-centimeter (0.4-inch) seam allowance.
Thread the cords through the casing. Attach a safety pin to one of the 1-meter (1.1-yard) long cords. Starting from the front-left hole, pull the cord all the way through the front and back casing, until it comes out the back-left hole. Repeat this step with the other cord, but for the other side; start at the front-right side, and finish at the back-right side.
The bag will close at the left and right sides, like a drawstring bag or pouch.
Knot the ends of the cords together. Take both of the cords on the left side of the bag, and knot the ends together. Repeat with the two cords on the right side of the bag.
Snip off any loose threads. Go over your bag, and snip off any loose or excess threads. Your bag is done, and ready to use!
If you want, you can attach a snap to the flap and front of the bag. Follow the instructions that come with the snap you are using, as each one will be a little different.